According to the World Meteorological Organization (WMO), an astonishing rise in the atmosphere's CO2 levels could create an approximate 66 foot rise in sea levels and add three degrees to temperatures. Today’s CO2 concentration of around 400ppm exceeds the natural variability seen over hundreds of thousands of years. WMO bulletin The organization said human CO2 emissions of coal, oil, cement, and deforestation reached an all-time high last year. The last time CO2 levels were this high was about three to five million years ago. A Bonn meeting next month will address new guidelines for the Paris climate agreement, which President Trump wants the United States to pull out of.